TARGET_OS_IPHONE and ApplicationTests

Question

Why doesn't this code work when compiling an ApplicationTests unit test bundle?

#if TARGET_OS_IPHONE
   #import <Foundation/Foundation.h>
   #import <UIKit/UIKit.h>
#else
   #import <Cocoa/Cocoa.h>
#endif

One of my dependencies has this check and compiles just fine in my main application bundles, but it tries to load <Cocoa/Cocoa.h> when compiling my ApplicationTests bundle. It's probably just my lack of understanding of Xcode, but I get nervous when my test bundles don't build. Any suggestions?

Answer 1

I had a similar problem: TARGET_OS_IPHONE isn't defined when building a static library. My solution was to add "-DTARGET_OS_IPHONE" to the "Other C Flags" section of the target build options.

Answer 2

You need to add

#import "TargetConditionals.h" 

source: https://opensource.apple.com/source/CarbonHeaders/CarbonHeaders-8A428/TargetConditionals.h.auto.html

Answer 3

The simplest solution is to move the #import <Foundation/Foundation.h> statement out if the #if condition and replace Cocoa with AppKit like this:

#import <Foundation/Foundation.h>
#if TARGET_OS_IPHONE
   #import <UIKit/UIKit.h>
#else
   #import <AppKit/AppKit.h>
#endif

The Foundation umbrella header imports the NSObjCRuntime header which in turn imports the TargetConditionals header.

Answer 4

It imposes no performance penalty, although it can hurt compile times. That said, it isn't really an issue for Objective C. However, it can really hurt when dealing with C++ classes.